A method of controlling an operation of an inlet valve system arranged in connection with each cylinder of an internal combustion piston engine, includes monitoring at least one parameter relating to engine load conditions, controlling using a primary control procedure an opening and closing timing of an inlet valve in response to the at least one parameter, and feeding charge air into the cylinder when the inlet valve is open. In a secondary control procedure a parameter relating to engine load conditions is measured and the closing timing of the inlet valve of the inlet valve system is controlled in response to the at least parameter independently from and with higher priority than the primary control procedure.

An aspect of the invention provides an exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode, the exhaust valve rocker arm assembly comprising: a rocker shaft that defines a pressurized oil supply conduit; a rocker arm configured to receive the rocker shaft and configured to rotate around the rocker shaft, the rocker arm including an oil supply passage defined in the rocker arm; a valve bridge configured to engage a first exhaust valve at a spherical elephant foot and a second exhaust valve at a cylindrical elephant foot; a hydraulic lash adjuster assembly, disposed on the rocker arm, including a first plunger body configured to extend rigidly and cooperatively engage with the valve bridge.

An aspect of the invention provides an exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode, the exhaust valve rocker arm assembly comprising: a rocker shaft that defines a pressurized oil supply conduit; a rocker arm configured to receive the rocker shaft and configured to rotate around the rocker shaft, the rocker arm including an oil supply passage defined in the rocker arm; a valve bridge configured to engage a first exhaust valve at a spherical elephant foot and a second exhaust valve at a cylindrical elephant foot; a hydraulic lash adjuster assembly, disposed on the rocker arm, including a first plunger body configured to extend rigidly and cooperatively engage with the valve bridge.

The invention relates to an internal combustion engine gas exchange valve actuator and is used to displace one or more internal combustion engine valves thereby improving the operation and extending the capabilities of the engine. The actuator includes a casing (2) attached to the engine head (1) and with a hollow cylinder (3) formed inside it and containing a reciprocating piston (6) with a piston rod. Provision is made in the casing (2) which is closed by a cap (4), for a loop for controlled charging and discharging of the pressurized fluid and for a solenoid valve with direct electromagnetic control. The solenoid valve is positioned above the piston (6) and is formed as a plunger (19) having a lower cylindrical widening with axial orifices (20) and an upper part with a central recess (22) and radial orifices (23) and (24).

The invention relates to an internal combustion engine gas exchange valve actuator and is used to displace one or more internal combustion engine valves thereby improving the operation and extending the capabilities of the engine. The actuator includes a casing (2) attached to the engine head (1) and with a hollow cylinder (3) formed inside it and containing a reciprocating piston (6) with a piston rod. Provision is made in the casing (2) which is closed by a cap (4), for a loop for controlled charging and discharging of the pressurized fluid and for a solenoid valve with direct electromagnetic control. The solenoid valve is positioned above the piston (6) and is formed as a plunger (19) having a lower cylindrical widening with axial orifices (20) and an upper part with a central recess (22) and radial orifices (23) and (24).

The invention relates to a locking device for a switchable valve drive component, including a first locking body and a second locking body which can be brought into engagement with one another or out of engagement in order to couple to one another or to uncouple two component parts arranged movably with respect to one another, wherein at least one of the two locking bodies has at least one curved surface. In order to increase the wear resistance of the locking device, provision is made for at least one of the two locking bodies to have a plurality of curved surfaces of which the respective curvature is described by radii of identical length having constructional center points spaced apart from one another.

The invention relates to a locking device for a switchable valve drive component, including a first locking body and a second locking body which can be brought into engagement with one another or out of engagement in order to couple to one another or to uncouple two component parts arranged movably with respect to one another, wherein at least one of the two locking bodies has at least one curved surface. In order to increase the wear resistance of the locking device, provision is made for at least one of the two locking bodies to have a plurality of curved surfaces of which the respective curvature is described by radii of identical length having constructional center points spaced apart from one another.

A hydraulic valve brake for a hydraulic valve drive of an internal combustion engine is provided. The valve brake includes a housing with a housing wall and with a housing base, and includes a piston which moves axially in the housing and one end side of which, together with the housing wall and the housing base, delimits a hydraulic pressure chamber and the other end side of which actuates a gas exchange valve. The housing wall is perforated in the region of the pressure chamber by one or more overflow openings, the opening cross sections of which are controlled by a control edge, which delimits the end side at the pressure chamber side, of the piston. In this case, it is the intention for the axial distance (h) between the control edge of the piston, when the latter is fully retracted into the housing, and the housing base to be set by a spacer of predetermined thickness (d).

A hydraulic valve brake for a hydraulic valve drive of an internal combustion engine is provided. The valve brake includes a housing with a housing wall and with a housing base, and includes a piston which moves axially in the housing and one end side of which, together with the housing wall and the housing base, delimits a hydraulic pressure chamber and the other end side of which actuates a gas exchange valve. The housing wall is perforated in the region of the pressure chamber by one or more overflow openings, the opening cross sections of which are controlled by a control edge, which delimits the end side at the pressure chamber side, of the piston. In this case, it is the intention for the axial distance (h) between the control edge of the piston, when the latter is fully retracted into the housing, and the housing base to be set by a spacer of predetermined thickness (d).

An exhaust valve rocker arm assembly operable in a combustion engine mode and an engine braking mode can include a rocker shaft and a rocker arm. The rocker shaft can define a pressurized oil supply conduit. The rocker arm can receive the rocker shaft and is configured to rotate around the rocker shaft. The rocker arm can have an oil supply passage defined therein. A valve bridge can engage a first exhaust valve and a second exhaust valve. In the engine braking mode, pressurized oil is communicated through the pressurized oil supply conduit, through the rocker arm oil supply passage and against an actuator such that a first plunger acts on the valve bridge during rotation of the rocker arm to a first angle opening the first valve a predetermined distance while the second valve remains closed.